1. Technical Field
The present invention relates to a ground engaging emergency brake system for a vehicle. The emergency brake system of the present invention is particularly useful for tractor-trailer rigs.
2. Description of the Prior Art
U.S. Pat. No. 4,325,465 discloses an auxiliary braking device for a highway tractor-trailer. The device has a drag shoe which comprises an elongated metal plate covered with a replaceable elastomeric sheath. The sheath has a high coefficient of friction with a road surface. The drag shoe is supported on the frame of the trailer transversely across the trailer in front of the rear wheels of the trailer. When released, the drag shoe is guided into the path of the rear wheels for the purpose of bringing the tractor-trailer to a stop. Most of the trailer weight on the drag shoe will be concentrated in the areas directly beneath the trailer tires limiting the effectiveness of the drag shoe.
A similar device is disclosed in U.S. Pat. No. 4,825,978.
The present invention is a ground engaging emergency brake and anti-jackknife system for a vehicle. The brake system comprises a brake skid which, in turn, comprises at least one elongated substantially planar rigid base member having upper and lower planar surfaces. A replaceable traction member is removably affixed to the base member lower planar surface. A linkage mechanism positions the brake skid, when fully deployed, in a ground engaging plane parallel to the plane of the vehicle, and when retracted, in a position adjacent to the underside of the vehicle. The vehicle has a longitudinal axis. The brake skid is centered along the longitudinal axis contiguous with the rear of said vehicle, preferably between the rear wheels of the vehicle. The system comprises an actuating mechanism for actuating the brake skid between said fully deployed and retracted positions. The actuating mechanism and linkage mechanism are effective to place at least a substantial amount of the vehicle weight on the brake skid when the brake skid is in its fully deployed position.
The present invention is particularly useful with a tractor-trailer rig.